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Detecting marine object is an attractive but challenging task in ocean exploration and conservation. Although the current popular object detection algorithms perform well in general. Because underwater images are affected by color projections and the scale of the object is usually smaller, the detection performance for marine object is not ideal. Therefore, this paper proposes an augmented weighted bidirectional feature pyramid network (AWBiFPN) that reduces the weakening of underwater image features and improves the integration efficiency of multi-scale feature, improving marine object detection performance. Specifically, this paper designs a multi-scale feature pyramid for efficient integration of feature information at all levels by combining weighted bidirectional integration pathway with designed Consistent Supervision module. Using Residual Feature Augmentation module to enhance the extraction of unchanging proportional contextual information, reduce the loss of information at the highest level of the feature map in the pyramid network and provide richer particulate characteristics for small-target detection. To scale the feature map and effectively utilize the feature information of different channels in the same spatial location, this article proposes the AWBiFPN layer, which replaces the depthwise separable convolution in the original BiFPN layer with conventional convolution. Evaluated on underwater image dataset (UTDAC), only 12 epochs are trained to 81.63% of mAP; experimented on MS COCO benchmark, achieving 37.9 AP. Meanwhile, the accuracy of the Aquarium Life dataset (AMLD) and underwater detection dataset under natural light (RUOD) are 81.41% mAP and 83.62% mAP, respectively. The results show that the method performed better not only in marine object detection but also in general class detection. • A novel feature pyramid network is proposed for marine object detection. • Three modules are designed to improve detection accuracy and efficiency. • Evaluation tests were conducted on four datasets. • Detection results of various structural designs are displayed. [ABSTRACT FROM AUTHOR]

• Silicone surfactant has excellent performance in reducing the surface tension of foam liquid. • Hydrophilic SiO 2 nanoparticles were modified to improve the stability of foam. • The addition of nanoparticles has a influence on the foam performance of hydrocarbon surfactants. • CTAB combined with nanoparticles can play a key role in stabilizing the foam. Foam has been widely used in coal mine dust control. However, its instability is still an issue in its application, and some surfactants components in foaming agents, such as fluorocarbons, are harmful to the environment. In this study, the environmentally friendly alkyl glycoside(APG0814) and cetyltrimethylammonium bromide (CTAB) were used as the foaming agents, and modified hydrophilic SiO 2 nanoparticles were added to improve foam stability. Also, the surface tension, foam properties, contact angle and intermolecular interaction of APG0814/CTAB/SiO 2 dispersion were studied. The experimental results showed that the appropriate concentration of CTAB combined with nanoparticles played a key role in stabilizing the foam. The surface tension of the foaming liquid increased with the increase in nanoparticles and CTAB, leading to the deterioration of foaming properties. The silicone surfactant GT-248 was added to the APG0814/CTAB/SiO 2 dispersion to further improve the surface activity of the foaming agent, and the effects of the silicone surfactant on the surface tension, foam properties, and wettability were studied systematically. The experimental results showed that the surface tension of the foaming agent decreased, and the foaming and wettability increased with the increase in silicone surfactant concentration. By the synergistic action of nanoparticles and surfactants, long-lasting and stable foam, fast coal dust deposition rate and low contact angle can be obtained. Among them, 0.8 wt%GT-248 was added to achieve the best surface activity, foaming ability and wettability. These fundamental results might guide the application of silicone surfactants combined with nanoparticle-hydrocarbon surfactants in mine dust control. [ABSTRACT FROM AUTHOR]

Abstract: An efficient copper-catalyzed N-arylation of N-arylsulfonamides with diaryliodonium salts is reported. The reaction employs diaryliodonium salts and N-arylsulfonamides in water at room temperature, giving the products in moderate to excellent yields. [Copyright &y& Elsevier]

This paper investigates the influence of task type and participatory structure (or classroom organisation) in pre-task planning on the fluency, complexity and accuracy of learners' oral production. 32 participants, divided into three experimental groups and one control group, carried out two tasks – a decision-making and an information-exchange task. The control group had no opportunity to plan while the experimental group participants planned for each task in one of the three planning conditions: pair work, individual or teacher-led. Individual task performances were scored for fluency, complexity and accuracy prior to statistical analysis. Results show that planning led to significantly superior performance than no planning across all dependent variables. Pair work planning significantly advantaged fluency compared to teacher-led planning but not accuracy or complexity. Consistent with previous research, teacher-led planning had some benefits for accuracy, and individual planning for complexity, but neither of these effects reached significance. The decision-making task, meanwhile, led to greater complexity than the information-exchange task. These results can be interpreted as implying that there are benefits in varying classroom organisation in pre-task planning, and that individual planning, whose value has sometimes been underestimated, should not be neglected. [Copyright &y& Elsevier]

Traditional object detection methods cannot effectively identify underwater objects with complex backgrounds, and it is difficult to fully obtain the details of small-scale underwater targets, resulting in poor detection performance. We propose a path-augmented Transformer detection framework to address these limitations to explore the semantic details of small-scale underwater targets in complex environments. On one hand, an embedded local path detection information scheme is devised to facilitate the interaction between high-level and low-level features, thereby enhancing the semantic representation of distinctive features of small-scale underwater targets. Rich dependency relationships are established between the acquired high-level and low-level features within the CSWin-Transformer framework, thus fortifying the semantic representation during the encoding phase. Furthermore, a individualized loss function is employed to optimize and fine-tune features at various hierarchical levels. On the other hand, a detection module with flexible and adaptive point representation that is different from conventional square detection methods is designed. This module covers the underwater target from any direction, and the salient point samples in classification localization and feature selection between points realize the feature selection improves the detection accuracy of underwater objects simultaneously. We designed a new weighted loss function to encourage the network to converge better. Experimental results on open-source underwater and remote sensing images of UTDAC, RUOD, and ADios show that the proposed method outperforms other underwater object detection methods in terms of precision(P), recall(R), comprehensive evaluation index of F1-score and FPS(frames per second). • A novel Path Enhanced Transformer is proposed for underwater object detection. • Added semantic representation of salient features of small-scale underwater Objects. • Designed a detection module with flexible, adaptive point representation. • A new weighted loss function is designed. • Evaluation tests were conducted on three datasets. [ABSTRACT FROM AUTHOR]

We demonstrate the dynamic evolution of multiple solitons (MSs) and noise-like pulse (NLP) in a passively mode-locked fiber laser using the nonlinear optical loop mirror (NOLM). The conversion from MSs to the NLP-soliton hybrid regime, as well as the conversion from the NLP-soliton hybrid regime to NLP, has been investigated with increasing the pump power. When the state converts from the MS regime to the hybrid regime, the NLP first appears as an intermittent feature of the laser emission, whose lifetime progressively increases, until it becomes permanent. While the conversion from the NLP-soliton hybrid regime to NLP is gradual. Moreover, the hybrid mode of dual-wavelength MSs and NLP is also obtained by adjusting the intra-cavity polarization and the pump power. These findings will constitute an impressive illustration of the connections and interactions between solitons and NLP from a passively mode-locked fiber laser. [ABSTRACT FROM AUTHOR]

Extent of resection (EOR) in glioma contributes to longer survival. The purpose of NCT01479686 was to prove whether intraoperative magnetic resonance imaging (iMRI) increases EOR in glioma surgery and benefit survival. Patients were randomized (1:1) to receive the iMRI (n = 161) or the conventional neuronavigation (n = 160). The primary endpoint was gross total resection (GTR); secondary outcomes reported were progression-free survival (PFS), overall survival (OS), and safety. 188 high-grade gliomas (HGGs) and 133 low-grade gliomas (LGGs) were enrolled. GTR was 83.85% in the iMRI group vs. 50.00% in the control group (P < 0.0001). In 321 patients, the median PFS (mPFS) was 65.12 months in the iMRI group and 61.01 months in the control group (P = 0.0202). For HGGs, mPFS was improved in the iMRI group (19.32 vs. 13.34 months, P = 0.0015), and a trend of superior OS compared with control was observed (29.73 vs. 25.33 months, P = 0.1233). In the predefined eloquent area HGG subgroup, mPFS, and mOS were 20.47 months and 33.58 months in the iMRI vs. 12.21 months and 21.16 months in the control group (P = 0.0098; P = 0.0375, respectively). From the exploratory analyses of HGGs, residual tumor volume (TV) < 1.0 cm3 decreased the risk of survival (mPFS: 18.99 vs. 9.43 months, P = 0.0055; mOS: 29.77 vs. 18.10 months, P = 0.0042). LGGs with preoperative (pre-OP) TV > 43.1 cm3 and postoperative (post-OP) TV > 4.6 cm3 showed worse OS (P= 0.0117) It showed that iMRI significantly increased EOR and indicated survival benefits for HGGs, particularly eloquent HGGs. Residual TV in either HGGs or LGGs is a prognostic factor for survival. • Using iMRI improved the chance of GTR in LGGs and HGGs. • iMRI in cerebral glioma surgery translated into prolonged PFS in HGGs. • Achieving GTR might extend PFS and OS of HGGs, particularly for eloquent HGGs. • Residual tumor volume in either HGGs or LGGs is a prognostic factor for survival. [ABSTRACT FROM AUTHOR]

Oil productions can result in pore pressure drop in the reservoir, generating an increase in effective stress and leading to reservoir compaction. The compaction in the subsurface reservoir translates to the earth's surface, which is manifested as a loss of elevation (land subsidence), causing damages to oil production facilities and surface infrastructures. The Liaohe oilfield, located in Liaohe River Delta (LRD), northeast of China, is one of the most significant subsidence areas in China as a direct consequence of oil extraction from the reservoir. Previous studies carried out in this area assumed the oil production-induced displacement retrieved from Interferometric Synthetic Aperture Radar (InSAR) corresponds only to vertical deformation. In this work, for the first time, we proposed a method to retrieve the full three-dimensional (3D) displacement field over the oilfield. We retrieved the vertical and east-west displacement components by combining the multiple-geometry InSAR line-of-sight (LOS) observations and retrieved the north-south component based on the assumption of a physical relationship between the horizontal and vertical displacement. Two ascending and two descending datasets from Sentinel-1 satellite covering the area were processed by an InSAR time series analysis over the 2017 to 2021 period, providing consistent displacement rate maps and displacement time series in the LOS direction. Spatial local-scale land subsidence was found in several producing fields over the deltaic region, including Shuguang, Huanxiling, and Jinzhou oilfields. The 3D displacement decomposition was then conducted in Shuguang oilfield. The derived 3D displacement field exhibit a circular subsidence bowl with a maximum subsiding rate reaching 212 mm/year, accompanied by a centripetal pattern of horizontal displacements with maximum rates up to 50–60 mm/year moving towards the subsidence center. The retrieved 3D displacements are in good agreement with predictions from the geomechanical modeling by assuming a disk-shaped reservoir subject to a uniform reduction in pore fluid pressure. Finally, we show the importance of knowing both the vertical and horizontal displacement in characterizing the lateral boundary of the subsurface reservoir. [ABSTRACT FROM AUTHOR]

Objectives To prospectively evaluate the diagnostic value of 3.0 Tesla magnetic resonance 3-dimensional sampling perfection with application-optimized contrast using different flip angle evolution (3D-SPACE) in the detection of sinus wall invasion and sinus patency in parasinus meningiomas. Methods In this study, 28 patients with suspected meningiomas adjacent to the venous sinus underwent conventional magnetic resonance imaging, contrast-enhanced magnetic resonance venography, and 3D-SPACE scans. We collected patient charts and surgical reports for demographic details, histologic analysis, and neurologic performance preoperatively and postoperatively. Images obtained by each technique were assessed independently by 2 neurosurgeons for characteristics of sinus infiltration, wall invasion, lumen patency, and collateral veins. Results The blood flow signal inside the lumen and collateral veins were depressed and presented as black, contrasting well with the sinus wall on 3D-SPACE imaging. When the curved-planar reconstruction images were combined, it was intuitive and accurate to detect the extent of sinus wall invasion by meningioma and also to detect lumen patency. An intratumoral "false lumen" was shown to maintain the blood flow inside the sinus at a totally invaded lesion. Moreover, collateral veins enveloped in a meningioma with their confluence points of the venous sinus were easily observed on 3D-SPACE images. Conclusion With an integrative presentation of parasinus meningioma, wall invasion, lumen patency, and collateral veins, high-resolution 3D-SPACE imaging provides a reliable technique to accurately assess venous sinus invasion preoperatively. Highlights • 3.0 Tesla 3D-SPACE imaging facilitates the detection of sinus invasion extent. • Curved planar reconstruction imaging is more intuitive for observation of patency. • Confluence between collateral vein and sinus can be shown by 3D-SPACE. • 3 months after operation is a better point in time for reexamination. [ABSTRACT FROM AUTHOR]

Postoperative continuous bloody cerebral spinal fluid drainage with external ventricular drainage catheter could decrease the incidence of inflammation. But the drainage catheter left in place will interrupt the watertight dura matter closure. To prevent the related cerebrospinal fluid leakage and subgaleal pseudomeningocele after the catheter removal, we developed a patched closure method to seal the dural outlet of the drainage catheter with a favorable clinical outcome. [ABSTRACT FROM AUTHOR]

We report on the observation of quasi-trapezoid noise-like pulses (NLPs) in a fiber laser with a large anomalous dispersion regime based on nonlinear polarization rotation. Trapezoidal NLPs operate at 1568 nm with a fundamental repetition rate of 946.14 kHz. The pulse width can widen from 12.54 to 32.17 ns, and the pulse energy can be increased from 8.81 to 25.84 nJ by increasing the pump power from 77.4 to 244.4 mW. The maximum intracavity energy of a trapezoidal pulse can reach ~258.4 nJ. Furthermore, stable high-order harmonics are obtained by regulating the pump power and polarization state. In the harmonic mode-locking regime, the second- to the tenth-order harmonic trapezoidal pulses can be achieved in the fiber laser. [ABSTRACT FROM AUTHOR]

Overexploitation and preliminary artificial breeding have led to an increasing interest in studying the reproductive biology and biochemical changes during gonad development in Oratosquilla oratoria. In this study, we established an accurate one-to-one correspondence between physical (and ovarian) morphology and ovarian histology during different maturity stages and improved the understanding of trophic dynamics with the progress of maturation, which will aid the aquaculture and artificial breeding techniques for this commercially important species. Based on ovarian histology and morphology, the ovaries were differentiated into six developmental stages, with five changes in color: immature stage (black), previtellogenesis (black), primary vitellogenesis (faint yellow), secondary vitellogenesis (golden yellow), maturation (light orange) and spent stage (brownish yellow). The visible colors of the median triangular structure of the telson can be used as an external morphological indicator of ovarian development status, and indicates that the females are near-ripe broods stocks when median triangular structure is almost filled with yellow. The gonadosomatic index (GSI) showed a statistically significant inverse correlation with the hepatopancreatic index (HPI) and muscle-somatic index (MSI). GSI significantly increased until stage III and HPI significantly decreased at stage II and recovered slowly thereafter. Nevertheless the MSI increased during the first two stages and decreased thereafter. A continuous decline in feeding intensity of females with ovarian development was found. The protein level in the muscle and hepatopancreas increased with protein accumulation in the ovary. Ovarian lipid concentration continued to increase, while, as in the hepatopancreas and muscle, lipid content decreased significantly at stage II and then recovered rapidly, followed by a sharp decline. Glycogen concentrations in the ovary kept steady, while in the hepatopancreas and muscle, there was a downward trend after a rise to the highest value. In conclusion, the energy for supporting ovarian development inevitably relies on energy reserves in the hepatopancreas and muscle and attention should be given to how to promote the transfer of organic reserves and energy to the ovaries during stock culture. • An accurate one-to-one correspondence between physical (and ovarian) morphology was established. • The visible colors of the median triangular structure of the telson can be used as an external morphological indicator of ovarian development status and the females are near ripe when median triangular structure is almost filled with yellow. • The gonadosomatic index (GSI) showed a statistically significant inverse correlation with the hepatopancreatic index (HPI) and muscle-somatic index (MSI). • A continuous decline in feeding intensity of females with ovarian development was found. • The energy for supporting ovarian development inevitably relies on energy reserves in the hepatopancreas and muscle. [ABSTRACT FROM AUTHOR]